<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        #big{
            width: 200px;
            height: 200px;
            background-color: green;
            overflow: hidden;
        }
        #big>div{
            width: 50px;
            height: 50px;
            background-color: purple;
            margin-left: 50px;
            margin-top: 50px;
        }
    </style>
</head>
<body>
<div id="big">
    <div></div>
</div>
</body>
</html>